Ducane Furnace Control Board Questions

Hello everyone and thank you for taking the time to look at this thread. Let me preface by saying that I made the mistake of trying test my control board without any knowledge of its working. I take full responsibility for my mistake. Now let me get to my problem.

I was using a multimeter to test the voltage on my Ducane furnace control board. I was originally doing it to test the voltage for the power supply to my Aprilaire solenoid. The furnace was running (blower and heat) when I used the multimeter on the wires where the thermostat runs to the board, specifically the red and white wires. I saw a spark, and the blower stopped, and then started again. Me being as dumb as I am, I did it again. It again sparked, but this time the blower stopped. It is no longer blowing or putting out hot air. There is a humming noise at the board which I guess means there's power to it. Any help would be appreciated as I have no heat, and it is very cold out. I have posted pictures of the board below as well as the furnace info. The wires I was testing are the thermostat ones on the left, the red and white.

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How old is your multitester and what condition is it in? Beat up? May have a short in it. If it is shorting even a small amount and you "hijacked" the load while it was running that may aggravate and damage the board. If the meter is questionable don't try it or use it again.